engine 19 slot

You are forgetting cost. slot supra 123 The Jet's price/speed ratio is pretty bad, and the five and six block engines are more efficient slot/speed as well Also the initial research investment for the Jet is steeper Example: 0 will either get you one 1slot Jet @ +9 5 knots, or one 3slot Refined Outboard @+26 3 knots